Percent Power on a Piper Aircraft
Flying the aircraft a little rich may not show percent power.
The DAU must have good signals from the following:
MAP
RPM
FUEL FLOW
OAT
PRESSURE ALTITUDE
You can verify all but the Pressure Altitude by just insuring you
Have them displayed on the MFD Engine Page.
The Percent Power will only work between (Approx) 50-80 %
Other than that it will display - - - - - -‘s
Engine Ground Run Test:
Run Engine to get about 33” of MAP.
This will be around 2400 RPM and approx 33 gallons
of Fuel Flow.
Slowly lean out the engine and around 26-27 gallons of Fuel Flow, the Percent indicator should come up.
Important Notes:
The MFD needs to be Set-Up to proper aircraft type.
If not set up correctly, the percent power indicator will
Not work. Check proper PPS and verify port assignments, on the
Port information page. Also take note of any CAS messages.
The Data Stream for % Power is sent from the PFD to the MFD via ARINC 429 RX4